The focus of this project is to explore the relationship between inflammatory cells and cognitive dysfunction in populations with HIV-1 infection. Extensive work has found that a biomarker is detected in lumbar cerebrospinal fluid of HIV(+) subjects with impaired cognition. Presently there are no suitable clinical tests to identify early neuro-inflammatory injury to neurons in such disorders as HIV-1 dementia. The ability to identify and treat HIV(+) populations before the onset of irreversible brain damage is highly desirable and forms the basis for this STTR proposal. ? ? ?